Bimodal parachute deployment system

ABSTRACT

A parachute deployment system is disclosed. In various embodiments, the system includes an interface configured to receive sensor information; a parachute load limiting device; and a parachute load limiting device state controller. The parachute load limiting device state controller sets a state of the parachute load limiting device to a state associated with a corresponding amount of load based at least in part on the sensor information.

CROSS REFERENCE TO OTHER APPLICATIONS

This application is a continuation of co-pending U.S. patent applicationSer. No. 15/338,086 entitled BIMODAL PARACHUTE DEPLOYMENT SYSTEM filedOct. 28, 2016 which is incorporated herein by reference for allpurposes.

BACKGROUND OF THE INVENTION

Parachutes are used to recover aircrafts in times of emergency.Conditions during the time of emergency can vary drastically. Differenttypes of parachutes may be suited for different conditions. Weightlimitations may prevent an aircraft from being outfitted with multiplevarying parachutes.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the invention are disclosed in the followingdetailed description and the accompanying drawings.

FIG. 1 is a diagram illustrating an embodiment of an aircraft comprisinga bimodal parachute deployment system before deployment.

FIG. 2A is a diagram illustrating an embodiment of an aircraftcomprising a load limiting device of a bimodal parachute deploymentsystem before the load limiting device is triggered.

FIG. 2B is a diagram illustrating an embodiment of an aircraftcomprising a load limiting device of a bimodal parachute deploymentsystem after the load limiting device is triggered.

FIG. 3A is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system.

FIG. 3B is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system after the load limitingdevice is triggered.

FIG. 4A is a diagram illustrating an embodiment of an aircraftcomprising a reefing device of a bimodal parachute deployment system ininitial stages of deployment.

FIG. 4B is a diagram illustrating an embodiment of an aircraftcomprising a reefing device of a bimodal parachute deployment systemafter the parachute is fully deployed.

FIG. 4C is a diagram illustrating an embodiment of a reefing device.

FIG. 4D is a diagram illustrating an embodiment of a reefing device.

FIG. 5A is a diagram illustrating an embodiment of a severing tool of abimodal parachute deployment system.

FIG. 5B is a diagram illustrating an embodiment of a severing tool of abimodal parachute deployment system.

FIG. 6A is a diagram illustrating an embodiment of a load limitingdevice and severing tool of a bimodal parachute deployment system priorto deployment.

FIG. 6B is a diagram illustrating an embodiment of a load limitingdevice and severing tool of a bimodal parachute deployment systemwherein the severing tool is triggered.

FIG. 6C is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system wherein a severing toolis not triggered.

FIG. 7A is a diagram illustrating an embodiment of a reefing device andsevering tool of a bimodal parachute deployment system prior todeployment.

FIG. 7B is a diagram illustrating an embodiment of a reefing device andsevering tool of a bimodal parachute deployment system wherein thesevering tool is triggered.

FIG. 7C is a diagram illustrating an embodiment of a reefing device of abimodal parachute deployment system wherein a severing tool is nottriggered.

DETAILED DESCRIPTION

The invention can be implemented in numerous ways, including as aprocess; an apparatus; a system; a composition of matter; a computerprogram product embodied on a computer readable storage medium; and/or aprocessor, such as a processor configured to execute instructions storedon and/or provided by a memory coupled to the processor. In thisspecification, these implementations, or any other form that theinvention may take, may be referred to as techniques. In general, theorder of the steps of disclosed processes may be altered within thescope of the invention. Unless stated otherwise, a component such as aprocessor or a memory described as being configured to perform a taskmay be implemented as a general component that is temporarily configuredto perform the task at a given time or a specific component that ismanufactured to perform the task. As used herein, the term ‘processor’refers to one or more devices, circuits, and/or processing coresconfigured to process data, such as computer program instructions.

A detailed description of one or more embodiments of the invention isprovided below along with accompanying figures that illustrate theprinciples of the invention. The invention is described in connectionwith such embodiments, but the invention is not limited to anyembodiment. The scope of the invention is limited only by the claims andthe invention encompasses numerous alternatives, modifications andequivalents. Numerous specific details are set forth in the followingdescription in order to provide a thorough understanding of theinvention. These details are provided for the purpose of example and theinvention may be practiced according to the claims without some or allof these specific details. For the purpose of clarity, technicalmaterial that is known in the technical fields related to the inventionhas not been described in detail so that the invention is notunnecessarily obscured.

A bimodal parachute deployment system is disclosed. The system comprisesan interface configured to receive sensor information, a parachute loadlimiting device, and a parachute load limiting device state controller.The parachute load limiting device state controller sets a state of theparachute load limiting device to a state associated with acorresponding amount of load based at least in part on the sensorinformation. In some embodiments, the parachute load limiting device hasmultiple states that correspond to varying amounts of load. For example,an engaged state may be a state wherein the parachute load limitingdevice constrains the load of the parachute to a predetermined limit. Adisengaged state may be a state wherein the parachute load limitingdevice does not affect the parachute's load.

Various conditions may require various types of parachutes in order torecover an object or aircraft. For example, an aircraft dropping at ahigh speed and high altitude may require a small parachute to ensure theparachute does not rip upon deployment whereas a large parachute may beappropriate in the event the aircraft is falling from a low altitude.The bimodal parachute deployment system may cause an appropriateparachute to be deployed based on present conditions.

In some embodiments, the parachute load limiting device decreases a loada parachute experiences upon initial deployment. For example, theparachute load limiting device may initially constrain the ability ofthe parachute to fully open. The load limiting device may increase theability of a tether of the parachute to absorb shock, decreasing theload on the parachute. The parachute may be used to recover an object,such as an aircraft. In some embodiments, the parachute load limitingdevice state controller engages or disengages the parachute loadlimiting device based on an altitude, speed, or flight trajectory of theobject to be recovered. The object or aircraft may comprise sensors thatgather information regarding altitude, speed, wind speed, flighttrajectory, environmental factors, obstacles or any other appropriatefactor.

FIG. 1 is a diagram illustrating an embodiment of an aircraft comprisinga bimodal parachute deployment system before deployment. The bimodalparachute deployment system may be stored on aircraft 100 to be used inthe event of an emergency. For example, the system may be triggered whenthe aircraft has a fatal engine failure. In the example shown, aircraft100 comprises bimodal parachute deployment system 108. Bimodal parachutedeployment system 108 comprises parachute 102, severing tool 104, andsensors 106. Parachute 102 may be stored in a container prior todeployment, such as a sack or a bucket. Parachute 102 may be folded andsecured with ties. Parachute load limiters may be stored alongside theparachute or as part of the parachute. Various parachute load limitersmay be used, such as reefing devices, shock absorbers, or any otherappropriate load limiting device.

Severing tool 104 may be stored near parachute 102. In some embodiments,severing tool 104 is the parachute load limiting device statecontroller. Severing tool 104 may be used to modify parachute 102 duringor prior to deployment. In various embodiments, various parachute loadlimiting device state controllers are used. The type of parachute loadlimiting device state controller used may be based upon a shape, aconfiguration, a material, an appropriate factor of the parachute loadlimiting device, or requirements of the flight vehicle.

Sensors 106 may include sensors attached to aircraft 100 at multiplepoints on the aircraft. Sensors 106 may comprise an accelerometer, agyroscope, a thermometer, a camera, sonar, radar, a camera, or any otherappropriate sensor. Sensors 106 may be used to gather informationregarding aircraft 100's position and flight trajectory. They may beused to gather information on surroundings of the aircraft andenvironmental obstacles.

FIG. 2A is a diagram illustrating an embodiment of an aircraftcomprising a load limiting device of a bimodal parachute deploymentsystem before the load limiting device is triggered. The load limitingdevice may expand in one dimension in the event pressure exerted uponthe device in the dimension reaches a predetermined threshold. In theexample shown, shock absorber 202 is used as a load limiting device.Parachute 206 has been deployed. Parachute 206 is attached to shockabsorber 202 via tether 204 at a topmost side of shock absorber 202.Tether 204 continues from below shock absorber 202 to split off into abridle that attaches to aircraft 200 at multiple points on the aircraft.Shock absorber 202 may be positioned between two separate sections oftether. In the example shown, parachute 206 is in initial stages ofdeployment. Parachute 206 may not be fully filled with air and may exertminimal amounts of force on tether 204.

FIG. 2B is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system after the load limitingdevice is triggered. In the example shown shock absorber 202 hasexpanded in length from its original length as shown in FIG. 2A.Parachute 206 has filled with air, causing the parachute to exert anupwards force on tether 204. In some embodiments, as parachute 206 fillswith air, the upwards force exerted on shock absorber 202 causes theshock absorber to expand vertically. Shock absorber 202's expansion mayalieve an initial load experienced by parachute 206, preventingparachute 206 from ripping due to sudden load as it inflates. A shockabsorber may be used when a parachute is deployed from an aircrafttraveling at a high altitude or high speed. The presence of the shockabsorber may be ideal for recovering the aircraft in certain conditionswhereas the absence of the shock absorber is desired in otherconditions.

FIG. 3A is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system. A shock absorber isshown. The shock absorber comprises tether 302 and fastener 300. Tether302 is folded and secured with fastener 200, decreasing the length ofthe tether. In some embodiments, tether 302 is attached to a parachuteat the top of the tether or attached to an aircraft at the bottom of thetether.

FIG. 3B is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system after the load limitingdevice is triggered. The load limiting device shown is a shock absorber.In the example shown, fastener 300 has split open. Tether 302 isreleased to its full length. In some embodiments, fastener 300 isconfigured to break open when a force exerted on tether 302 reaches apredetermined threshold. The fastener may break based on an amount offorce exerted in a vertical direction on tether 302. As the fastenerbreaks and the tether extends to its full length, load or shockdelivered to an object attached to the topmost end of tether 302 may bedecreased. In various embodiments, shock absorbers of variousconfigurations may be used. The shock absorber may be made of synthetic,cloth-like, or rope-like material. The shock absorber may be insertedbetween sections of parachute tether in order to decrease load to aparachute. Multiple shock absorbers may be placed at different points ona parachute's tethers.

FIG. 4A is a diagram illustrating an embodiment of an aircraftcomprising a reefing device of a bimodal parachute deployment system ininitial stages of deployment. The reefing device may be used as a loadlimiting device for the parachute. In the example shown, parachute 404has been deployed from aircraft 400. The reefing device may be hollowand elliptical in shape. In the example shown, reefing device 402 issituated around parachute 404, constraining the size of the parachute.The initial volume of parachute 404 upon deployment may be determined bythe size of reefing device 402. The reefing device may protect theparachute from ripping. For example, a parachute may split open uponinitial deployment in the event air rushing into the parachute is toopowerful for fabric of the parachute to handle. Large, thin parachutesmay be ideal for low altitudes and low speeds but be susceptible tobreakage. A reefing device may allow a large, thin parachute to beadaptable to high altitudes and high speeds. A reefing device may becomposed of plastic, metal, composites, or any other appropriatematerial.

FIG. 4B is a diagram illustrating an embodiment of an aircraftcomprising a reefing device of a bimodal parachute deployment systemafter the parachute is fully deployed. In the example shown, parachute404 is fully inflated and is attached to aircraft 400. Reefing device402 is situated at a base of parachute 404. Reefing device 402 mayrestrict a size of an opening at the bottom of parachute 404, causingthe parachute to inflate slowly. As the parachute inflates, the reefingdevice may slide down the parachute.

FIG. 4C is a diagram illustrating an embodiment of a reefing device. Inthe example shown, parachute 450 is deployed with reefing device 452.Reefing device 452 as shown is positioned below a canopy of parachute450. The reefing device holds tethers of the parachute close together.The reefing device prevents the canopy from inflating fully anddecreases an amount of load on the parachute.

In some embodiments, a reefing device includes a line that is accessibleby a severing device on the aircraft. Cutting the line may cause thereefing device to fall down or fall off. The severing device may be usedto disengage the reefing device after the parachute is initiallydeployed with the reefing device engaged. The severing device mayinclude a timer. The severing device may cut a component of the reefingdevice after a predetermined amount of time has passed since parachutedeployment. In some embodiments, severing the reefing device allows aparachute to sufficiently slow down its vehicle, human, or other objectbefore impact. The ability to engage or disengage the reefing devicebefore or during deployment may be critical to successful recovery.

FIG. 4D is a diagram illustrating an embodiment of a reefing device. Inthe example shown, reefing device 452 is at the bottom of tethers ofparachute 450. In some embodiments, reefing device 452 slides down thetethers slowly as the parachute inflates with air. In some embodiments,reefing device 452 is released and falls to the bottom of the tethersbased on a timer-triggered process or is disengaged by a load limitingdevice state controller.

FIG. 5A is a diagram illustrating an embodiment of a severing tool of abimodal parachute deployment system. The severing tool may be used as aload limiting device state controller. The severing tool may be used tocut off a load limiting device. In some embodiments, the parachute loadlimiting device state controller severs a component of the parachuteload limiting device in order to set the parachute load limiting deviceto a disengaged state. For example, cutting a load limiting device offof a parachute prior to deployment prevents the load limiting devicefrom affecting the parachute's deployment. The load limiting devicestate controller may perform an action that permanently affects the loadlimiting device. For example, cutting a component of the load limitingdevice may prevent the device from ever being used effectively. In someembodiments, the load limiting device state controller performs anaction on the load limiting device to enable or disable it that can bereversed.

In the example shown, severing tool 500 is a U-shape. In someembodiments, a load limiting device state controller comprises a blade.The blade may be stored within the tool. In the event the severing toolis triggered, the blade may extrude and cut an object placed inside thesevering tool. The blade may be retractable. The severing tool may beconfigured to surround an object that is required to be severed. Thesevering tool may be used or not used based on conditions prior toparachute deployment.

FIG. 5B is a diagram illustrating an embodiment of a severing tool of abimodal parachute deployment system. In the example shown, severing tool500 comprises blade 502. Blade 502 may cut through an object placedwithin the severing tool. The shape of the severing tool may prevent theblade from being exposed to objects besides an intended object. Forexample, the left side of blade 502 as shown may be blunt whereas thebottom edge of the blade is sharp.

In various embodiments, various configurations of severing tools may beused. The blade may be exposed or the tool may be rectangular in shape.The tool may comprise an exposed blade that is attached to a frame of anaircraft. The blade may be originally positioned downward in a positionwherein it is able to cut a desired object. The blade may beautomatically shifted upwards to a position where it cannot encounterthe desired object in the event the severing tool is not to be used. Thesevering tool may comprise an explosive. The tool may vary in size andmay be attached to the aircraft in various locations.

FIG. 6A is a diagram illustrating an embodiment of a load limitingdevice and severing tool of a bimodal parachute deployment system priorto deployment. A parachute load limiting device state controller may seta parachute load limiting device to one of two states. The two statesmay comprise an engaged state wherein the parachute load limiting deviceis utilized and a disengaged state wherein the parachute load limitingdevice is not utilized. The parachute load limiting device statecontroller may set the parachute load limiting device to an engagedstate in the event an object of interest is determined to be at a highaltitude or a high speed. The parachute load limiting device statecontroller may set the parachute load limiting device to a disengagedstate in the event an object of interest is determined to be at a lowaltitude or a low speed.

The parachute load limiting device may be engaged as a default state. Inthe example shown, severing tool 604 surrounds fastener 602. Fastener602 holds tether 600 in a bundled configuration as a shock absorber. Insome embodiments, the parachute load limiting device state controllerdoes not perform an action in the event the parachute load limitingdevice is to be set to an engaged state. A blade of severing tool 604may remain retracted in the event the parachute is desired to bedeployed with the shock absorber intact. A parachute attached to tether600 may be deployed with the shock absorber.

FIG. 6B is a diagram illustrating an embodiment of a load limitingdevice and severing tool of a bimodal parachute deployment systemwherein the severing tool is triggered. In some embodiments, theparachute load limiting device state controller severs a component ofthe parachute load limiting device in the event the parachute loadlimiting device state controller sets the parachute load limiting deviceto a disengaged state. In the example shown, a blade of severing tool604 is brought down to cut off fastener 602. The shock absorber on thetether of the parachute is released. Fastener 602 is detached fromtether 600, allowing the tether to reach its full length. Tether 600 isattached to parachute 606.

In some embodiments, a parachute load limiting device state controlleris controlled automatically based on the sensor information. Forexample, severing tool 604 may be triggered to cut fastener 602 in theevent a speed of the aircraft falls below a predetermined threshold. Theparachute load limiting device state controller may comprise amechanical switch or electronic components. A flight computer mayanalyze signals received from sensors and send a command to the loadlimiting device state controller. The process may be handledautomatically due to slow human reaction times.

In some embodiments, the parachute load limiting state controller iscontrolled by a pilot or other human. A pilot of an aircraft may use thebimodal parachute deployment system to modify parachutes based onrecovery conditions. For example, a pilot may press a button, pull alevel, or otherwise send a command that controls the severing tool.

FIG. 6C is a diagram illustrating an embodiment of a load limitingdevice of a bimodal parachute deployment system wherein a severing toolis not triggered. In the event that the parachute is determined to bedeployed with the load limiting device engaged, the severing tool maynot cut off a shock absorber. In the example shown, parachute 634 isdeployed with shock absorber 630 on parachute tether 632.

FIG. 7A is a diagram illustrating an embodiment of a reefing device andsevering tool of a bimodal parachute deployment system prior todeployment. In the example shown, severing tool 700 surrounds a portionof reefing device 702. Reefing device 702 may be cylindrical orring-like. Reefing device 702 surrounds parachute container 704. In someembodiments, a reefing device may be stored inside of a parachutecontainer. A severing tool may be configured to have access to thereefing device prior to parachute deployment, regardless of where thereefing device is stored.

FIG. 7B is a diagram illustrating an embodiment of a reefing device andsevering tool of a bimodal parachute deployment system wherein thesevering tool is triggered. In some embodiments, the parachute loadlimiting device state controller cuts a reefing device from a parachuteprior to parachute deployment. In the example shown, reefing device 702has been severed. Severing tool 700 has its blade exposed. A blade of asevering tool may retract after being used to cut an object. Parachute708 is fully filled with air.

FIG. 7C is a diagram illustrating an embodiment of a reefing device of abimodal parachute deployment system wherein a severing tool is nottriggered. In the event the severing tool does not cut off the reefingdevice, the parachute deploys with the reefing device. As shown,parachute 734 is partially filled with air. It is constrained by reefingdevice 732, which surrounds it. The severing tool may not cut off thereefing device due to environmental or flight conditions.

In some embodiments, two or more parachute load limiting devices areused as part of a bimodal parachute deployment system. Two or moreparachute load limiting device state controllers may be used. Aparachute load limiting device may be paired with a parachute loadlimiting device state controller. The system may include a load limitingdevice state controller that is controlled automatically and anotherload limiting device state controller that is controlled by a human.

Although the foregoing embodiments have been described in some detailfor purposes of clarity of understanding, the invention is not limitedto the details provided. There are many alternative ways of implementingthe invention. The disclosed embodiments are illustrative and notrestrictive.

What is claimed is:
 1. A parachute load limiting device comprising: atether configured to be coupled to a parachute line at an end and to becoupled to an aircraft at an opposite end, wherein in an initial statethe tether is folded to decrease a length of the tether; a fastenerconfigured to: hold folds of the tether in place in the initial state,and open to permit the tether to extend in length and decrease a loaddelivered to a parachute; and a reefing device configured to be situatedaround a mid-section of a canopy of the parachute to constrain a size ofthe parachute in the initial state, wherein the reefing device isconfigured to slide down the canopy to a bottom of the parachute to holdone or more tethers of the parachute together.
 2. The device of claim 1,wherein the parachute load limiting device is configured to be insertedbetween sections of the parachute line to decrease load to theparachute.
 3. The device of claim 1, further comprising a severing toolconfigured to break the fastener to permit the tether to extend inlength.
 4. The device of claim 1, further comprising a blade configuredto break the fastener to permit the tether to extend in length.
 5. Thedevice of claim 1, comprising one or more additional parachute loadlimiting devices or one or more additional fasteners.
 6. The device ofclaim 1, further comprising a state controller that engages theparachute load limiting device prior to deployment of the parachute. 7.The device of claim 1, further comprising a state controller thatdisengages the parachute load limiting device prior to deployment of theparachute.
 8. The device of claim 1, further comprising a statecontroller that engages the parachute load limiting device afterdeployment of the parachute.
 9. The device of claim 1, furthercomprising a state controller that disengages the parachute loadlimiting device after deployment of the parachute.
 10. The device ofclaim 1, further comprising a state controller that operates thefastener based on a timer.
 11. The device of claim 1, wherein the forceis below the threshold when a vehicle in which the parachute loadlimiting device is provided does not exceed a threshold altitude or athreshold speed.
 12. The device of claim 1, wherein the force meets thethreshold when a vehicle in which the parachute load limiting device isprovided exceeds a threshold altitude or a threshold speed.
 13. Thedevice of claim 1, wherein the parachute load limiting device statecontroller severs a component of the parachute load limiting device inthe event the parachute load limiting device state controller sets theparachute load limiting device to a disengaged state.
 14. The device ofclaim 1, further comprising a state controller configured to instructthe fastener to permit the tether to extend in length in response tosensor information including at least one of: environmental factors,obstacles, wind speed, altitude, or velocity.
 15. The device of claim14, wherein the state controller is controlled automatically based onthe sensor information.
 16. The device of claim 1, wherein the parachuteload limiting device has an engaged state in which the fastener isoperated and a disengaged state in which the fastener is not operated.17. The device of claim 16, wherein the parachute load limiting deviceis engaged as a default state.
 18. A method, comprising: providing atether that couples to a parachute line at an end and couples to anaircraft at an opposite end, wherein in an initial state the tether isfolded to decrease a length of the tether; providing a fastener that:holds folds of the tether in place in the initial state, and opens topermit the tether to extend in length and decrease a load delivered to aparachute; and providing a reefing device that is situated around amid-section of a canopy of the parachute to constrain a size of theparachute in an initial state, wherein the reefing device slides downthe canopy to a bottom of the parachute to hold one or more tethers ofthe parachute together.
 19. The method of claim 18, further comprising:providing a severing tool that breaks the fastener to permit the tetherto extend in length.
 20. The method of claim 18, further comprising:providing a state controller that instructs the fastener to permit thetether to extend in length in response to sensor information includingat least one of: environmental factors, obstacles, wind speed, altitude,or velocity.